Synchronization signal periodicity adjustment

ABSTRACT

Methods, systems, and devices for wireless communications are described. Different periodicities may be dynamically selected when monitoring and transmitting signaling used for link management, where respective periodicities may be based on the quality of the link between devices. For instance, a first wireless device may use a first monitoring periodicity to monitor for signals transmitted from another wireless device. Upon determining that a link condition has changed (e.g., decreased or reached a threshold), the first wireless device may decrease its monitoring periodicity (and increase monitoring frequency) to detect signals transmitted by the other wireless device more frequently. In such cases, the other wireless device may likewise transmit its measurement signals more often (e.g., in accordance with a second periodicity) based on the link quality. The adjusted monitoring and transmission periodicities may provide additional occasions for the wireless device to detect signals from another device.

CROSS REFERENCE

The present application for patent claims the benefit of U.S.Provisional Patent Application No. 62/835,431 by LI et al., entitled“SYNCHRONIZATION SIGNAL PERIODICITY ADJUSTMENT,” filed Apr. 17, 2019,assigned to the assignee hereof, and expressly incorporated herein.

INTRODUCTION

The following relates generally to wireless communications, and morespecifically to synchronization signal configurations.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

SUMMARY

A method of communications at a first device is described. The methodmay include determining a configuration of an actual transmissionperiodicity and at least one virtual transmission periodicity used by asecond device. The method may include selecting a monitoring periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters. Themethod may include monitoring for one or more measurement signalstransmitted by the second device over a communication link in accordancewith the selected monitoring periodicity.

An apparatus for communications at a first device is described. Theapparatus may include a processor, and memory coupled to the processor.The processor and memory may be configured to determine a configurationof an actual transmission periodicity and at least one virtualtransmission periodicity used by a second device. The processor andmemory may be configured to select a monitoring periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters. Theprocessor and memory may be configured to monitor for one or moremeasurement signals transmitted by the second device over acommunication link in accordance with the selected monitoringperiodicity.

Another apparatus for communications at a first device is described. Theapparatus may include means for determining a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity used by a second device. The apparatus may include means forselecting a monitoring periodicity corresponding to the actualtransmission periodicity or the at least one virtual transmissionperiodicity based on one or more parameters. The apparatus may includemeans for monitoring for one or more measurement signals transmitted bythe second device over a communication link in accordance with theselected monitoring periodicity.

A non-transitory computer-readable medium storing code forcommunications at a first device is described. The code may includeinstructions executable by a processor to determine a configuration ofan actual transmission periodicity and at least one virtual transmissionperiodicity used by a second device. The code may include instructionsexecutable by a processor to select a monitoring periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters. Thecode may include instructions executable by a processor to monitor forone or more measurement signals transmitted by the second device over acommunication link in accordance with the selected monitoringperiodicity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more parametersinclude a link condition.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the link condition includesan error rate for information transmitted over the communication link.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining a linkcondition of the communication link between the first device and thesecond device.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for selecting themonitoring periodicity to correspond to the actual transmissionperiodicity.

Some examples may further include operations, features, means, orinstructions for determining that a link condition satisfies athreshold, and adjusting the monitoring periodicity to correspond to theat least one virtual transmission periodicity based on the linkcondition satisfying the threshold, the at least one virtualtransmission periodicity being shorter than the actual transmissionperiodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for starting a timer basedon adjusting the monitoring periodicity to correspond to the at leastone virtual transmission periodicity. Some examples may further includeoperations, features, means, or instructions for determining that thetimer may have expired, and monitoring for the one or more measurementsignals transmitted from one or more other devices based on the timerexpiring.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that thelink condition satisfies a second threshold, and adjusting themonitoring periodicity to correspond to the actual transmissionperiodicity based on the link condition satisfying the second threshold.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that thecommunication link may have failed based on a link condition,establishing a connection with one or more other devices based on thefailed communication link, and receiving the one or more measurementsignals from the one or more other devices.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicationthat the second device may be transmitting the one or more measurementsignals in accordance with the at least one virtual transmissionperiodicity. Some examples may further include operations, features,means, or instructions for selecting the monitoring periodicity tocorrespond to the at least one virtual transmission periodicity based onthe indication.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for selecting themonitoring periodicity to correspond to the at least one virtualtransmission periodicity based on a link condition, and transmitting, tothe second device, an indication that the monitoring periodicitycorresponds to the at least one virtual transmission periodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for operating in a firstmonitoring mode associated with the actual transmission periodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for operating in a secondmonitoring mode associated with the at least one virtual transmissionperiodicity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the configurationof the actual transmission periodicity and the at least one virtualtransmission periodicity may include operations, features, means, orinstructions for receiving an indication of the configuration via radioresource control (RRC) signaling.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the one ormore measurement signals from the second device based on the monitoring.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more measurementsignals include synchronization signal blocks (SSBs), or channel stateinformation reference signals (CSI-RSs), or sounding reference signals(SRSs), or a combination thereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first device includes afirst node in an integrated access and backhaul (IAB) network and thesecond device includes a second node in the IAB network.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the communication linkincludes one or more directional beams operating over a millimeter wave(mmW) radio frequency spectrum band.

A method of communications at a first device is described. The methodmay include determining a configuration of an actual transmissionperiodicity and at least one virtual transmission periodicity. Themethod may include selecting a transmission periodicity corresponding tothe actual transmission periodicity or the at least one virtualtransmission periodicity based on one or more parameters. The method mayinclude transmitting one or more measurement signals to a second deviceover a communication link in accordance with the selected transmissionperiodicity.

An apparatus for communications at a first device is described. Theapparatus may include a processor, and memory coupled to the processor.The processor and memory may be configured to determine a configurationof an actual transmission periodicity and at least one virtualtransmission periodicity. The processor and memory may be configured toselect a transmission periodicity corresponding to the actualtransmission periodicity or the at least one virtual transmissionperiodicity based on one or more parameters. The processor and memorymay be configured to cause the apparatus to transmit one or moremeasurement signals to a second device over a communication link inaccordance with the selected transmission periodicity.

Another apparatus for communications at a first device is described. Theapparatus may include means for determining a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity. The apparatus may include means for selecting atransmission periodicity corresponding to the actual transmissionperiodicity or the at least one virtual transmission periodicity basedon one or more parameters. The apparatus may include means fortransmitting one or more measurement signals to a second device over acommunication link in accordance with the selected transmissionperiodicity.

A non-transitory computer-readable medium storing code forcommunications at a first device is described. The code may includeinstructions executable by a processor to determine a configuration ofan actual transmission periodicity and at least one virtual transmissionperiodicity. The code may include instructions executable by a processorto select a transmission periodicity corresponding to the actualtransmission periodicity or the at least one virtual transmissionperiodicity based on one or more parameters. The code may includeinstructions executable by a processor to transmit one or moremeasurement signals to a second device over a communication link inaccordance with the selected transmission periodicity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more parametersinclude a link condition.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining a linkcondition of the communication link between the first device and thesecond device.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for selecting thetransmission periodicity to correspond to the actual transmissionperiodicity. Some examples may further include operations, features,means, or instructions for determining that a link condition satisfies athreshold, and adjusting the transmission periodicity to correspond tothe at least one virtual transmission periodicity based on the linkcondition satisfying the threshold, the at least one virtualtransmission periodicity being shorter than the actual transmissionperiodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for starting a timer basedon adjusting the transmission periodicity to correspond to the at leastone virtual transmission periodicity. Some examples may further includeoperations, features, means, or instructions for determining that thetimer may have expired, and transmitting, to one or more other devices,an indication to transmit the one or more measurement signals inaccordance with the at least one virtual transmission periodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that thelink condition satisfies a second threshold, and adjusting thetransmission periodicity to correspond to the actual transmissionperiodicity based on the link condition satisfying the second threshold.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to one ormore other devices, an indication to transmit the one or moremeasurement signals in accordance with the at least one virtualtransmission periodicity based on a link condition.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to one ormore other devices, symbol timing information for transmitting the oneor more measurement signals.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for selecting thetransmission periodicity to correspond to the at least one virtualtransmission periodicity based on a link condition, and transmitting, tothe second device, an indication that the transmission periodicitycorresponds to the at least one virtual transmission periodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicationthat the second device may be monitoring for the one or more measurementsignals in accordance with the at least one virtual transmissionperiodicity. Some examples may further include operations, features,means, or instructions for selecting the transmission periodicity tocorrespond to the at least one virtual transmission periodicity based onthe indication.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for operating in a firsttransmission mode associated with the actual transmission periodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for operating in a secondtransmission mode associated with the at least one virtual transmissionperiodicity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting theconfiguration of the actual transmission periodicity and the at leastone virtual transmission periodicity may include operations, features,means, or instructions for transmitting an indication of theconfiguration via RRC signaling.

A method of communications at a first device is described. The methodmay include transmitting one or more measurement signals to a first setof one or more devices in accordance with a transmission periodicity.The method may include receiving, from a second device, an indication toadjust the transmission periodicity to at least one virtual transmissionperiodicity based on one or more parameters of a communication linkbetween the second device and a second set of one or more devices. Themethod may include transmitting the one or more measurement signals to asecond set of one or more devices in accordance with the at least onevirtual transmission periodicity.

An apparatus for communications at a first device is described. Theapparatus may include a processor, and memory coupled to the processor.The processor and memory may be configured to transmit one or moremeasurement signals to a first set of one or more devices in accordancewith a transmission periodicity. The processor and memory may beconfigured to receive, from a second device, an indication to adjust thetransmission periodicity to at least one virtual transmissionperiodicity based on one or more parameters of a communication linkbetween the second device and a second set of one or more devices. Theprocessor and memory may be configured to transmit the one or moremeasurement signals to a second set of one or more devices in accordancewith the at least one virtual transmission periodicity.

Another apparatus for communications at a first device is described. Theapparatus may include means for transmitting one or more measurementsignals to a first set of one or more devices in accordance with atransmission periodicity. The apparatus may include means for receiving,from a second device, an indication to adjust the transmissionperiodicity to at least one virtual transmission periodicity based onone or more parameters of a communication link between the second deviceand a second set of one or more devices. The apparatus may include meansfor transmitting the one or more measurement signals to a second set ofone or more devices in accordance with the at least one virtualtransmission periodicity.

A non-transitory computer-readable medium storing code forcommunications at a first device is described. The code may includeinstructions executable by a processor to transmit one or moremeasurement signals to a first set of one or more devices in accordancewith a transmission periodicity. The code may include instructionsexecutable by a processor to receive, from a second device, anindication to adjust the transmission periodicity to at least onevirtual transmission periodicity based on one or more parameters of acommunication link between the second device and a second set of one ormore devices. The code may include instructions executable by aprocessor to transmit the one or more measurement signals to a secondset of one or more devices in accordance with the at least one virtualtransmission periodicity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more parametersinclude a link condition.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving aconfiguration of at least one virtual transmission periodicity used bythe second device, the configuration being received prior to theindication from the second device, where the at least one virtualtransmission periodicity may be a based on the configuration.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining aconfiguration of the at least one virtual transmission periodicity.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from asecond device, symbol timing information, and transmitting the one ormore measurement signals to the second set of one or more devices basedon the symbol timing information.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the at least one virtualtransmission periodicity may be shorter than the transmissionperiodicity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first wireless deviceincludes a first node in an IAB network and the second wireless deviceincludes a second node in the IAB network.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports synchronization signal periodicity adjustment inaccordance with one or more aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports synchronization signal periodicity adjustment in accordancewith one or more aspects of the present disclosure.

FIG. 3 illustrates an example of transmission/monitoring modes thatsupport synchronization signal periodicity adjustment in accordance withone or more aspects of the present disclosure.

FIG. 4 illustrates an example of a process flow in a system thatsupports synchronization signal periodicity adjustment in accordancewith one or more aspects of the present disclosure.

FIGS. 5 and 6 show block diagrams of devices that supportsynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure.

FIG. 7 shows a block diagram of a communications manager that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure.

FIG. 8 shows a diagram of a system including a UE that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure.

FIG. 9 shows a diagram of a system including a base station thatsupports synchronization signal periodicity adjustment in accordancewith one or more aspects of the present disclosure.

FIGS. 10 through 14 show flowcharts illustrating methods that supportsynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure.

DETAILED DESCRIPTION

Wireless communication systems may operate in mmW frequency ranges,e.g., 28 gigahertz (GHz), 40 GHz, 60 GHz, etc. Wireless communicationsat these frequencies may be associated with increased signal attenuation(e.g., pathloss), which may be influenced by various factors, such astemperature, barometric pressure, diffraction, blockage, etc. As aresult, signal processing techniques, such as beamforming, may be usedto coherently combine energy and overcome the pathlosses at thesefrequencies. Due to the increased amount of pathloss in mmWcommunication systems, transmissions between wireless devices may bebeamformed. A receiving device may also use beamforming techniques toconfigure antenna(s) and/or antenna array(s) such that transmissions arereceived in a directional manner.

Some wireless communications systems may include access nodes tofacilitate wireless communications between a network and various nodesand devices, such as UEs. Such deployments may use beamformedtransmissions in mmW frequency ranges for communications betweendifferent nodes, which may include access and backhaul communications.For instance, a parent node (which may also be referred to as a donornode, an anchor node, or other like terminology) may have ahigh-capacity, wired, backhaul connection (e.g., fiber) to a corenetwork. The parent node may also communicate (e.g., using directionalbeams) with one or more other nodes (e.g., relay nodes or devices)and/or UEs that may be referred to as child nodes. As such, wirelesscommunications between the parent node and other devices may includebackhaul communications, access communications, or a combinationthereof. Such systems may be referred to as an IAB network.

In deployments supporting both access and backhaul over wirelesscommunication links (e.g., in an IAB network), a child node may rely onsignaling (e.g., SSBs, CSI-RSs, or the like) to acquire beam informationfrom potential IAB parent nodes. For instance, to acquire beaminformation, SSBs may be transmitted by one or more parent nodes in acertain time interval, and each SSB may be identified by a unique numberreferred to as an SSB index. Each SSB may be transmitted via a specificbeam radiated in a respective direction, where one or more SSBs may beincluded within a synchronization signal burst. Other wireless devices(e.g., UEs and other nodes) located near the parent nodes may measurethe signal strength of each SSB detected for a period of time, and thewireless devices may identify the SSB index with the strongest signalstrength (where the strongest signal strength may correspond to the bestbeam for the wireless device relative to other beams used by the parentnode). Likewise, a parent node may rely on signaling (e.g., SRSstransmitted in the uplink from child nodes for beam management andchannel quality estimation.

However, conditions may exist that may cause interference, blockage,etc. of the beam carrying measurement signals, such as an SSB, which mayresult in a link failure. In these conditions, the ability of the childnode to receive the SSB may be negatively impacted. For example, if thepath between the parent node and the child node is blocked, the childnode may be unable to rely on the SSB to re-acquire its parent node. Assuch, latency in the network (e.g., for nodes recovering from a linkfailure) may be based on the rate and/or frequency of SSB transmissions.In one example, a node that transmits SSBs more frequently mayfacilitate robust acquisition/re-acquisition opportunities for anothernode or UE. However, there also may be overhead associated withtransmitting SSBs more often. As a result, there may be a tradeoffbetween signaling overhead and system stability and reliability.

As described herein, upon the detection of a beam or link failure, thechild node and parent node may dynamically switch autonomously orsynchronously to a different monitoring and transmission frequencymodes. For example, a child node or a parent node, or a combinationthereof, may monitor the link condition of a communication link betweenthe child node and the parent node. In some examples, if one or both ofthe nodes determine that the link condition has fallen below apre-defined threshold (e.g., as a result of decreased or poor linkconditions from interference), then either or both nodes may attempt tosignal the other node indicating the poor link condition. If the othernode is able to receive the indication, then both nodes maysynchronously switch to a different mode, enabling a relatively higherfrequency for signal transmissions and monitoring.

Additionally or alternatively, if the nodes are unable to receive theindication (e.g., due to the link conditions), then the two nodes mayautonomously switch to a different mode based on the link quality. Forexample, in a first mode, SSB transmissions and monitoring may occurwith a first periodicity and more frequently than a second mode (e.g.,where SSB monitoring and transmissions may occur according to aperiodicity associated with link conditions that are greater than thethreshold). There may also be any number of different modes that may bedynamically selected based on the current link condition. The flexibleselection of different periodicities for signal transmissions andcorresponding monitoring that may change dynamically according to linkconditions may allow for increased reliability in the network, reducedlatency (e.g., in acquiring or reacquiring a parent node), and reducedor minimized signaling overhead.

Aspects of the disclosure are initially described in the context of awireless communications system. Specific examples are then described forsynchronization signal periodicity adjustment in an IAB communicationnetwork. Aspects of the disclosure are further illustrated by anddescribed with reference to apparatus diagrams, system diagrams, andflowcharts that relate to synchronization signal periodicity adjustment.

FIG. 1 illustrates an example of a wireless communications system 100that supports synchronization signal periodicity adjustment inaccordance with one or more aspects of the present disclosure. Thewireless communications system 100 includes base stations 105, UEs 115,and a core network 130. In some examples, the wireless communicationssystem 100 may be an LTE network, an LTE-A network, an LTE-A Pronetwork, or a NR network. In some cases, wireless communications system100 may support enhanced broadband communications, ultra-reliable (e.g.,mission critical) communications, low latency communications, orcommunications with low-cost and low-complexity devices. Wirelesscommunications system 100 may support the use of dynamically selectedmonitoring and transmission periodicities for measurement signals.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB orgiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up a portion of the geographic coverage area 110,and each sector may be associated with a cell. For example, each basestation 105 may provide communication coverage for a macro cell, a smallcell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for UEs 115 include entering a powersaving “deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300GHz. Generally, the region from 300 MHz to 3 GHz is known as theultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features. However, the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter range (e.g., less than 100 km) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that may be capable of toleratinginterference from other users.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support mmW communications between UEs 115and base stations 105, and EHF antennas of the respective devices may beeven smaller and more closely spaced than UHF antennas. In some cases,this may facilitate use of antenna arrays within a UE 115. However, thepropagation of EHF transmissions may be subject to even greateratmospheric attenuation and shorter range than SHF or UHF transmissions.Techniques disclosed herein may be employed across transmissions thatuse one or more different frequency regions, and designated use of bandsacross these frequency regions may differ by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a carrieraggregation configuration in conjunction with component carriersoperating in a licensed band (e.g., LAA). Operations in unlicensedspectrum may include downlink transmissions, uplink transmissions,peer-to-peer transmissions, or a combination of these. Duplexing inunlicensed spectrum may be based on frequency division duplexing (FDD),time division duplexing (TDD), or a combination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving device is equipped with one or moreantennas. MIMO communications may employ multipath signal propagation toincrease the spectral efficiency by transmitting or receiving multiplesignals via different spatial layers, which may be referred to asspatial multiplexing. The multiple signals may, for example, betransmitted by the transmitting device via different antennas ordifferent combinations of antennas. Likewise, the multiple signals maybe received by the receiving device via different antennas or differentcombinations of antennas. Each of the multiple signals may be referredto as a separate spatial stream, and may carry bits associated with thesame data stream (e.g., the same codeword) or different data streams.Different spatial layers may be associated with different antenna portsused for channel measurement and reporting. MIMO techniques includesingle-user MIMO (SU-MIMO) where multiple spatial layers are transmittedto the same receiving device, and multiple-user MIMO (MU-MIMO) wheremultiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based atleast in in part on a signal that was transmitted in different beamdirections. For example, a UE 115 may receive one or more of the signalstransmitted by the base station 105 in different directions, and the UE115 may report to the base station 105 an indication of the signal theUE 115 received with a highest signal quality, or an otherwiseacceptable signal quality. Although these techniques are described withreference to signals transmitted in one or more directions by a basestation 105, a UE 115 may employ similar techniques for transmittingsignals multiple times in different directions (e.g., for identifying abeam direction for subsequent transmission or reception by the UE 115),or transmitting a signal in a single direction (e.g., for transmittingdata to a receiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a set of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a set of antenna elements of an antennaarray, any of which may be referred to as “listening” according todifferent receive beams or receive directions. In some examples, areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based on listeningaccording to different receive beam directions (e.g., a beam directiondetermined to have a highest signal strength, highest signal-to-noiseratio, or otherwise acceptable signal quality based on listeningaccording to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer mayperform packet segmentation and reassembly to communicate over logicalchannels. A Medium Access Control (MAC) layer may perform priorityhandling and multiplexing of logical channels into transport channels.The MAC layer may also use hybrid automatic repeat request (HARQ) toprovide retransmission at the MAC layer to improve link efficiency. Inthe control plane, the RRC protocol layer may provide establishment,configuration, and maintenance of an RRC connection between a UE 115 anda base station 105 or core network 130 supporting radio bearers for userplane data. At the Physical layer, transport channels may be mapped tophysical channels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s)=1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)), and may be positionedaccording to a channel raster for discovery by UEs 115. Carriers may bedownlink or uplink (e.g., in an FDD mode), or be configured to carrydownlink and uplink communications (e.g., in a TDD mode). In someexamples, signal waveforms transmitted over a carrier may be made up ofmultiple sub-carriers (e.g., using multi-carrier modulation (MCM)techniques such as orthogonal frequency division multiplexing (OFDM) ordiscrete Fourier transform spread OFDM (DFT-S-OFDM)).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).For example, communications over a carrier may be organized according toTTIs or slots, each of which may include user data as well as controlinformation or signaling to support decoding the user data. A carriermay also include dedicated acquisition signaling (e.g., synchronizationsignals or system information) and control signaling that coordinatesoperation for the carrier. In some examples (e.g., in a carrieraggregation configuration), a carrier may also have acquisitionsignaling or control signaling that coordinates operations for othercarriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum and, in some examples, the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may consist ofone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 and/or UEs 115 that support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communications system 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation or multi-carrier operation. A UE 115 may beconfigured with multiple downlink component carriers and one or moreuplink component carriers according to a carrier aggregationconfiguration. Carrier aggregation may be used with both FDD and TDDcomponent carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including wider carrier or frequency channel bandwidth, shortersymbol duration, shorter TTI duration, or modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a suboptimal or non-ideal backhaullink). An eCC may also be configured for use in unlicensed spectrum orshared spectrum (e.g., where more than one operator is allowed to usethe spectrum). An eCC characterized by wide carrier bandwidth mayinclude one or more segments that may be utilized by UEs 115 that arenot capable of monitoring the whole carrier bandwidth or are otherwiseconfigured to use a limited carrier bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than othercomponent carriers, which may include use of a reduced symbol durationas compared with symbol durations of the other component carriers. Ashorter symbol duration may be associated with increased spacing betweenadjacent subcarriers. A device, such as a UE 115 or base station 105,utilizing eCCs may transmit wideband signals (e.g., according tofrequency channel or carrier bandwidths of 20, 40, 60, 80 MHz) atreduced symbol durations (e.g., 16.67 microseconds). A TTI in eCC mayconsist of one or multiple symbol periods. In some cases, the TTIduration (that is, the number of symbol periods in a TTI) may bevariable.

Wireless communications system 100 may be an NR system that may utilizeany combination of licensed, shared, and unlicensed spectrum bands,among others. The flexibility of eCC symbol duration and subcarrierspacing may allow for the use of eCC across multiple spectrums. In someexamples, NR shared spectrum may increase spectrum utilization andspectral efficiency, specifically through dynamic vertical (e.g., acrossthe frequency domain) and horizontal (e.g., across the time domain)sharing of resources.

Wireless communications system 100 may include access nodes tofacilitate wireless communication between various wireless devices (suchas UEs 115 and other access nodes or base stations 105) and the corenetwork 130. For example, an anchor access node (or parent node) mayhave a high-capacity, wired (e.g., fiber), backhaul connection to thenetwork, while communicating simultaneously with one or more otheraccess nodes (e.g., base stations 105, relay devices, UEs 115), whichmay be referred to as child nodes. Due to a variety of conditions, thechannel (or path) between the communicating devices may experienceinterference, blockage, etc., such that the wireless communications maydegrade or fail. Such conditions may include adverse weather,temperature, barometric pressure, diffraction, physical objects, etc.These conditions may affect the ability of parent and child nodes tocommunicate over the channel.

However, as described herein, techniques may be used by various wirelessdevices within wireless communications system 100 to select differentperiodicities for monitoring for signaling transmitted by anotherwireless device, which may be based on the quality of the link betweenthe devices. For instance, a first wireless device (e.g., a UE 115 or abase station 105) may use a particular monitoring periodicity to monitorfor signals transmitted from another wireless device based on currentlink conditions. Upon determining that a link quality has changed (e.g.,decreased or reached a threshold), the first wireless device maydecrease its monitoring periodicity (e.g., increase a monitoringfrequency) to attempt to detect signals transmitted by the otherwireless device. Further, the other wireless device may likewisedecrease its transmission periodicity (and increase a transmissionfrequency) of measurement signals (e.g., SSBs) due to the changed linkquality in an attempt to assist the wireless device in detecting thetransmitted signals. As a result, the increased monitoring andtransmission periodicities may provide additional occasions for thewireless device to identify signals that facilitate efficient and stablecommunication links (e.g., measurement reporting, beam management) undervarious conditions. Additionally, should the condition of the linkimprove, the wireless devices may select a different transmissions andmonitoring periodicity commensurate with the current link condition(e.g., a lower frequency in cases where the link quality is above aminimum threshold).

One or more of the UEs 115 may include a communications manager 101,which may determine a configuration of an actual transmissionperiodicity and at least one virtual transmission periodicity used by aparent node. In some cases, the communications manager 101 may determinea link condition of a communication link between the child node and theparent node. The communications manager 101 may select a monitoringperiodicity corresponding to the actual transmission periodicity or avirtual transmission periodicity based on one or more parameters, andmonitor for measurement signals transmitted by the parent node over thecommunication link in accordance with the selected monitoringperiodicity. In some cases, the one or more parameters include the linkcondition.

One or more of the base stations 105 may include a communicationsmanager 101, which may determine a configuration of an actualtransmission periodicity and a virtual transmission periodicity. In somecases, the communications manager 101 may determine a link condition ofa communication link between the parent node and a child node. Thecommunications manager 101 may select a transmission periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters, andtransmit measurement signals to the child node over the communicationlink in accordance with the selected transmission periodicity. In somecases, the one or more parameters include the link condition.

The parent node may also communicate with a nearby node (e.g.,neighboring node). The neighboring node may also include acommunications manager 101, which may transmit measurement signals towireless devices (e.g., child node, parent node, or combination thereof)in accordance with a transmission periodicity, receive, from a parentnode, an indication to adjust the transmission periodicity to a virtualtransmission periodicity based on one or more parameters of acommunication link between the parent node and the wireless devices, andtransmit the measurement signals to the wireless devices in accordancewith the virtual transmission periodicity. In some cases, the one ormore parameters include a link condition.

FIG. 2 illustrates an example of a wireless communications system 200that supports synchronization signal periodicity adjustment inaccordance with one or more aspects of the present disclosure. Wirelesscommunications system 200 (which may be an example of an NR system thatsupports mmW communications) may supplement wireline backhaulconnections (e.g., wireline backhaul links 220) by sharinginfrastructure and spectral resources for network access with wirelessbackhaul link capabilities, providing an IAB network architecture.Wireless communications system 200 may include a core network 205 andbase stations 105 or supported devices split into one or more supportentities (i.e., functionalities) for promoting wireless backhaul densityin collaboration with communication access. Aspects of the supportingfunctionalities of the base stations 105 may be referred to as IABnodes, such as IAB donor nodes 210 and IAB relay nodes 215. Wirelesscommunications system 200 may additionally support a number of UEs 115,which may communicate on the uplink with one or more IAB donor nodes210, IAB relay nodes 215, or a combination of these devices. In someexamples, wireless communications system 200 may implement aspects ofwireless communications system 100.

Wireless communications system 200 may include one or more IAB donornodes 210, which may interface between a wireline network and a wirelessnetwork. In some cases, an IAB donor node 210 may be referred to as ananchor node, as the IAB donor node 210 anchors the wireless network to awireline connection. For example, each IAB donor node 210 may include atleast one wireline backhaul link 220 and one or more additional links(e.g., wireless backhaul links 225, backup wireless backhaul links 230,access links 235). An IAB donor node 210 may be split into associatedbase station centralized unit (CU) and distributed unit (DU) entities,where one or more DUs associated with an IAB donor node 210 may bepartially controlled by an associated CU. CUs of IAB donor nodes 210 mayhost layer 3 (L3) (e.g., RRC, service data adaption protocol (SDAP),PDCP) functionality and signaling. Furthermore, CUs of IAB donor nodes210 may communicate with the core network 205 over a wireline backhaullink 220 (e.g., which may be referred to as an NG interface). DUs mayhost lower layer operations, such as layer 1 (L1) and/or layer 2 (L2)(e.g., RLC, MAC, physical (PHY) layer) functionality and signaling. A DUentity of an IAB donor node 210 may support a serving cell within thenetwork coverage area according to connections associated with wirelessbackhaul links 225 and access links 235 of the IAB network. DUs of theIAB donor nodes 210 may control both access and backhaul links withinthe corresponding network coverage and may provide controlling andscheduling for descendant (i.e., child) IAB relay nodes 215 and or UEs115. For example, a DU may support an RLC channel connection with a UE115 (e.g., via an access link 235) or with an IAB relay node 215 (e.g.,via a backhaul link, such as a primary wireless backhaul link 225 or abackup wireless backhaul link 230).

IAB relay nodes 215 may be split into associated mobile terminal (MT)and base station DU entities, where MT functionality of the IAB relaynodes 215 may be controlled and/or scheduled by antecedent (i.e.,parent) IAB nodes via wireless backhaul links. A parent node to a relaynode 215 may be another (antecedent) relay node 215 or an IAB donor node210. The MT functionality may be similar to functionality performed byUEs 115 in the system. An IAB relay node 215 may not be directlyconnected to a wireline backhaul 220. Instead, the IAB relay node 215may connect to the core network 205 via other IAB nodes (e.g., anynumber of additional IAB relay nodes 215 and an IAB donor node 210)using wireless backhaul links. The IAB relay node 215 may transmitupstream (e.g., towards the core network 205) in the IAB system using MTfunctionality. In some cases, DUs of the IAB relay nodes 215 may bepartially controlled by signaling messages from CU entities of anassociated IAB donor node 210 (e.g., transmitted via an Fl-applicationprotocol (AP)). The DUs of the IAB relay nodes 215 may support servingcells of the network coverage area. For example, a DU of an IAB relaynode 215 may perform the same or similar functions as a DU of an IABdonor node 210, supporting one or more access links 235 for UEs 115, oneor more wireless backhaul links for downstream IAB relay nodes 215, orboth.

Wireless communications system 200 may employ relay chains forcommunications within the IAB network architecture. For example, a UE115 may communicate with an IAB node, and the IAB node may relay thedata to a base station CU or the core network 205 either directly or viaone or more IAB relay nodes 215. Each IAB relay node 215 may include aprimary wireless backhaul link 225 for relaying data upstream and/orreceiving information from a base station CU or the core network 205. Insome cases, an IAB relay node 215 may additionally include one or morebackup wireless backhaul links 230 (e.g., for redundant connectivityand/or improved robustness). If the primary wireless backhaul link 225fails (e.g., due to interference, malfunction at a connected IAB node,movement of IAB nodes, maintenance at IAB nodes), an IAB relay node 215may utilize a backup wireless backhaul link 230 for backhaulcommunication within the IAB network.

The first (e.g., primary) wireless backhaul link 225 may be associatedwith a coverage area and MT functionality may be controlled and/orscheduled by a first parent node. The one or more secondary backhaullinks (e.g., backup wireless backhaul links 230) may be associated witha non-collocated coverage area and controlled and/or scheduled by one ormore parent nodes. Each of the primary backhaul connections and the oneor more secondary connections may support spectral capabilities toprovide network communication over one or more RATs. The one or more IABnodes may further support base station DU entities and may supportmultiple backhaul and access links within the relay chain. The DUentities may control and/or schedule descendant IAB relay nodes 215 andUEs 115 within the IAB network (e.g., downstream in the IAB network) viathe configured backhaul and access links. That is, an IAB relay node 215may act as a relay between an IAB donor node 210 and one or moredescendant devices (e.g., other IAB relay nodes 215, UEs 115) in bothcommunication directions based on established backhaul and accessconnections. It should be noted that the various devices in wirelesscommunications system 200 may act as parent nodes, child nodes, or bothbased on the system architecture, and these roles may change dynamicallyfor each device.

In some cases, wireless devices (e.g., IAB nodes) may operate in one ofmore pathloss modes such as a high pathloss mode when the pathloss valuesatisfies (or exceeds) a threshold pathloss value or a normal (e.g.,low) pathloss mode when the pathloss value is below the thresholdpathloss value. For instance, one or more wireless devices may performwireless communications in the wireless communications system 200 over aradio frequency spectrum band. In some aspects, this may include thewireless device(s) operating in a first pathloss mode (e.g., a lowpathloss mode or normal mode) in the wireless communications system 200.

The wireless device(s) may receive a signal that indicates that thepathloss value has satisfied (or exceeded) a threshold pathloss value.As one example, the wireless device(s) may monitor a channel of theradio frequency spectrum band (e.g., monitor signals being communicatedover the channel) and determine that the pathloss value has satisfied(or exceeded) the threshold pathloss value. In another example, thewireless device(s) may receive a signal from another wireless deviceindicating that the pathloss value has satisfied (or exceeded) thethreshold pathloss value. Accordingly, the wireless device(s) may switchfrom the first pathloss mode (e.g., a low pathloss mode) to a secondpathloss mode (e.g., high pathloss mode) and continue to performwireless communications. The second pathloss mode (e.g., the highpathloss mode) may include one or more parameters to support continuedwireless communications in the high pathloss environment. Examples ofthe parameters that may be adjusted may include, but are not limited to,the length of the SSB in the high pathloss mode being longer, the lengthof a reference signal in the high pathloss mode being longer, amodulation and coding scheme (MCS) in the high pathloss mode beinglower, and the like. Accordingly, the wireless devices may continue toperform wireless communications in the wireless communications system200 in the high pathloss environment according to the second pathlossmode (e.g., the high pathloss mode).

A UE 115 or relay node 215 may rely on an SSB to acquire beaminformation from a current or potential parent node, such as a donornode 210 or a relay node 215. An SSB may consist of a primarysynchronization signal (PSS), a secondary synchronization signal (SSS),and/or broadcast information (e.g., a physical broadcast channel(PBCH)). To acquire beam information, multiple SSBs may be transmittedby one or more parent nodes (e.g., over wireless backhaul links 225 orover access links 235) in some time interval, and each SSB may beidentified by a unique number referred to as an SSB index. Each SSB maybe transmitted via a specific beam radiated in a certain direction,where one or more SSBs may be included within a synchronization signalburst. Other wireless devices (e.g., UEs 115 and other nodes) locatedaround the parent nodes may measure the signal strength of each SSBdetected for a certain period and the wireless devices may identify theSSB index with the strongest signal strength (where the strongest signalstrength may correspond to the most ideal beam for the wireless devicerelative to other beams used by the parent node).

In some cases, an access link 235 (e.g., between a donor node 210, relaynode 215, UE 115, or a combination thereof) or a wireless backhaul link225 carrying an SSB may be negatively impacted due to interference,blockage, etc. In these conditions, the ability of a UE 115 or relaynode 215 to receive SSB transmissions may be affected, which may causelatency in the network, increased overhead, and decreased networkreliability. Therefore, a relay node 215, UE 115, donor node 210, or acombination thereof, may monitor the access link 235 condition (orwireless backhaul link 225 condition) between itself and another node orUE 115. If any of the nodes determine that the link condition has fallenbelow a threshold (e.g., a predetermined threshold), then any or allnodes may attempt to signal the other nodes or UEs 115 indicating thepoor link condition. If the other nodes or UEs 115 are able to receivethe indication, then the nodes may synchronously switch to a differentmode. If the other nodes or UEs 115 are unable to receive theindication, then the nodes may autonomously switch to a different mode.For example, in a different mode, SSB transmissions and monitoring mayoccur more frequently. There also may be any number of different modesthat may be dynamically selected based on the current link condition.The increased frequency of SSB transmission that may change dynamicallyaccording to link conditions may allow for increased reliability in thenetwork, latency may be reduced, and overhead may be minimized.

FIG. 3 illustrates an example of transmission/monitoring modes 300 thatsupport synchronization signal periodicity adjustment in accordance withone or more aspects of the present disclosure. In some examples, thetransmission/monitoring modes 300 may implement aspects of wirelesscommunications system 100. The transmission/monitoring modes 300 mayinclude a first frequency mode 305 and second frequency mode 310. Eachfrequency mode 305 and 310 may include a number of virtual instances 315and actual instances 320, which may correspond to the transmission of anSSB 325 (e.g., during a TTI). A virtual transmission periodicity mayrefer to a period of time between virtual instances 315 of a signal, andan actual transmission periodicity may refer to a period of time betweenactual instances 320 of a signal.

In some cases, first frequency mode 305 may correspond to a firsttransmission/monitoring periodicity 330-a (e.g., in accordance with anactual transmission periodicity), and second frequency mode 310 maycorrespond to a second transmission/monitoring periodicity 330-b (e.g.,in accordance with a virtual transmission periodicity) that is shorterthan (e.g., higher frequency than) the first transmission/monitoringperiodicity 330-a. As illustrated, a virtual transmission periodicitymay have a higher frequency than an actual transmission periodicity.However, the virtual instances 315 and the actual instances 320, as wellas the virtual and actual periodicities, may be different than what isillustrated.

The first frequency mode 305 and second frequency mode 310 may beexamples of modes enabling different periodicities used forcommunication in an IAB network between donor nodes 210, relay nodes215, UEs 115, or a combination thereof as described in FIG. 2. Asdescribed herein, donor nodes 210 may be referred to as parent nodes andrelay nodes 215 may be referred to as child nodes. In some cases, nodesand UEs 115 in an IAB network may rely on an SSB 325 transmitted from acurrent or potential parent node to acquire beam information. However,these nodes may experience blocking, interference, or a combinationthereof that may inhibit the nodes from receiving SSB 325 reliably.

In these cases, the frequency of SSB 325 transmission and monitoring maybe a dynamic parameter such that, when connectivity is poor between achild and parent node, the SSB 325 may be transmitted more frequently.Similarly, when connectivity is not affected by interference, or whenthe connection quality returns to a certain threshold, the SSB 325transmission frequency may decrease to a base level or first frequencymode 35. There may be several different SSB 325 transmission frequenciesthat may be implemented under various network conditions. For example,under non-adverse conditions, the SSB 325 may be transmitted at a lowfrequency or not at all, while under slightly adverse conditions, theSSB 325 may be transmitted at a slightly higher frequency, and underextremely adverse conditions, the SSB 325 may be transmitted at a highfrequency. Different thresholds for various levels of adverse conditionsmay be pre-configured and paired with different SSB 325 transmissionfrequencies.

The frequency adjustment from a first frequency mode 305 to a secondfrequency mode 310 (and back to the first frequency mode 305) may bedynamic such that there may be any number of modes used to adjust thelink conditions and detected errors present. For example, a firstfrequency mode 305 may be a lower frequency mode (e.g., utilizing thefirst transmission/monitoring periodicity 330-a) that is used when lessadverse conditions are present, and a second frequency mode 310 may be ahigh frequency mode (e.g., utilizing the second transmission/monitoringperiodicity 330-b that is shorter than first transmission/monitoringperiodicity 330-a) that may be used when strongly adverse conditions arepresent. There may also be any of number of modes in between the firstand second frequency to be used dependent on the current conditions ofthe connection between the parent node and child node. Similarly, awireless device may transmit and/or monitor for signals in every virtualinstance 315 (e.g., using a respective mode). In some cases, the childnode and parent node may also use signaling other than an SSB 325, suchas a CSI-RS, as one example. In some cases, the child node may transmitan SRS or other signaling on the uplink to the parent node in accordancewith the first frequency mode or the second frequency mode (and theirrespective periodicities 330).

In some implementations, the parent node and the child node may agreeupon the timing and frequency of actual instances 320 and virtualinstances 315. An actual instance 320 may correspond to resourcesallocated for the transmission and reception of data signaling, and mayoccur less frequently than virtual instances 315 that may be resourcesallocated for the transmission and reception of an SSB in adverseconditions. In some cases, this agreement may extend to other nodes orUEs 115 in the network. The agreement may be made upon setup of theconnection between the child node and parent node and may be based onexchange of capabilities or monitoring requirements between the nodes,or there may be a particular configuration supported by both nodes thatis known prior to enabling a high-pathloss mode. Under non-adverseconditions the parent node may transmit in the actual instances 320 andthe child node may monitor the actual instances 320. If the parent nodedetects poor link quality, the parent node may switch to transmitting inthe virtual instances 315 that occur more often than the actualinstances 320. If the child node detects poor link quality, the childnode may switch to monitoring the virtual instances 315.

Either a child node or a parent node may detect a beam or link failure.This detection may be based on error rate, lack of receivingacknowledgments (ACKs) (or increased reception of negativeacknowledgments (NACKs)), measurements performed based on SSBs todetermine radio link failure, low reference signal received power(RSRP), failure to decode a channel due to signal quality, lower thanexpected signal to interference-plus-noise ratio (SINR) or signal tonoise ratio (SNR), or the like. In one example, the parent node mayreceive a high number of NACKs from the child node, indicating thatthere may be a poor connection between the child node and parent node.In some cases, there may be a pre-determined threshold for the number ofNACKs that may be received by the parent node before changing SSB 325transmission frequencies. Likewise, there may be a threshold for thenumber of NACKs transmitted by the child node before the child nodeswitches to a second frequency mode 310.

In another example, between the SSBs 325, the child node and parent nodemay transmit and receive data during the actual instances 320 and thetwo nodes may measure an error rate during the actual instances 320. Oneor both of the nodes may conclude that the error rate has increased outof a pre-determined range and may conclude that poor link qualityexists. Upon the detection of beam or link failure, the node may switchto a different SSB frequency mode. In some implementations, the nodethat first detects the poor connection may transmit a signal to theother node indicating there is a poor connection, that the node isswitching modes, or a combination thereof. For example, the parent nodemay transmit data to the child node, and the child node may recognizethat there is a problem with the link and adjust a monitoringperiodicity. As such, the child node may transmit one or more NACKs tothe parent node. If the parent node is able to receive the one or moreNACKs, the parent nodes may also transition to the higher frequency modefor transmitting SSBs 325.

In other cases, the parent node may detect the poor link quality beforethe child node. The parent node may indicate, to the child node, thatthe parent node is switching modes. The parent node may then switchmodes and transmit an SSB 325 more frequently. In some cases, the parentnode may switch modes without transmitting an indication to the childnode. The child node may switch modes upon receiving SSBs 325 at thehigher frequency, upon receiving an indication from the parent node thatthe parent node is switching modes, or a combination thereof. In somecases, the child node may monitor every virtual instance 315 and actualinstance 320 independent of the mode the parent node is in. In somecases, the parent node may only transmit an SSB 325 when there is a poorlink condition between parent and child nodes.

In some examples, the child node may not receive transmissions from theparent node or may recognize the link quality is poor, switch itsmonitoring periodicity 330, and stop transmitting ACKs and NACKs. Inthis case, the child node may be monitoring at a high frequency (e.g.,using the second transmission/monitoring periodicity 330-b) and theparent node may be transmitting at the first frequency mode 305 (e.g.,using the first transmissions/monitoring periodicity 330-a). For aperiod of time, the child node and parent mode may be out of sync suchthat one node is in a first frequency mode 305 and the other is in ahigher or second frequency mode 310. For example, the child node mayswitch to a second frequency mode 310 and may not receive the SSB 325 ina time frame the child node is expecting because the parent node has notswitched modes and/or periodicities yet.

In some cases, the child node may utilize a timer that starts when thechild node switches to the second frequency mode 310. When the timer isrunning, the child node may continue to monitor for the SSB 325 from theparent node to account for the time it may take for the parent node torealize poor link quality exists and to switch modes. There may also bea timer that the parent node utilizes such that, if the parent node hasnot received an ACK or a NACK from the child node in a certain timeperiod, the parent node may switch to a second frequency mode 310 uponexpiration of the timer. Mode switching at the parent node or child nodemay be autonomous if the detection of the poor link quality is notsynchronous between the nodes, such as in the case previously described.The parent node and child node may also autonomously or synchronouslyswitch back to a first frequency mode 305 when the link quality returns.In any case, the flexibility for the various nodes to switch betweentransmission and monitoring periodicities may account for a variety ofconditions that a communications link may experience, enabling bothsynchronous and asynchronous behavior, while also facilitating fast ordelayed switching that may be dynamically based on the link conditions.

In some implementations, all beams between the parent node and childnode may be blocked. In this case, the parent node may indicate to oneor more other IAB nodes near the parent node (e.g., neighboring nodes)to increase their SSB transmission frequency. The parent node maytransmit this indication immediately after switching modes, after acertain number of attempts to communicate with the child node, as soonas a link condition threshold is satisfied, after an amount of timeafter detecting poor link quality, or a combination thereof. The parentnode may also signal neighboring nodes if the parent node does not havethe capability to transmit SSB 325 at a higher frequency. For example,the parent node may not have enough resources available to accommodatethe higher transmission frequency.

In some cases, the child node may be able to monitor SSB 325transmissions from multiple nodes and may be able to receive an SSB 325from its parent node, a neighboring node, or a combination thereof. Ifthe child node receives an SSB 325 from a node that is not its parent,and does not receive an SSB 325 from the parent node, then the childnode may switch to the neighboring node. If the child node receives anSSB 325 from both a parent and neighboring node then the child node maycontinue to communicate with the parent node or may switch to theneighboring node. The neighboring nodes that may be indicated to switchtransmission frequencies and the different transmission frequency ratesmay be pre-configured or may be determined on-demand. Through theincreased frequency of signals sent by neighboring nodes, a child nodemay be able to receive beam management signaling (or other signaling)despite decreased link quality or a link failure with a parent node,enabling robust communications within the system.

In some examples, such as when the communication link(s) between theparent and child node decrease in quality or fail, timing informationmay also be transmitted to one or more neighboring nodes. For instance,while the parent node and child nodes are able to communicate over acommunication link and receive SSBs 325 (e.g., with varyingperiodicities 330, as described herein), both the parent and the childnode may operate using synchronous communications. More specifically,when monitoring for a signal from the parent node, a child node may knowwhen a signal is transmitted by the parent node (and vice versa).However, should the condition of a communication link degrade,synchronization may be lost between the nodes. As a result, the parentnode may transmit, to one or more neighboring nodes, timing information(e.g., symbol timing information) used for communicating with the childnode. As described above, the neighboring node(s) may receive a requestfrom the parent node to transmit measurement signals, and may also beprovided with the symbol timing information from the parent node. Assuch, the measurement signals may be transmitted by a neighboring nodeto the child node in accordance with the symbol timing information, andthe child node may monitor for the measurement signal using the samesymbol timing. That is, the parent node may provide its symbol timinginformation to the neighboring node so that the neighboring node maytransmit signals at or near the symbol time that the child node will bemonitoring for signals, thereby enabling continuous synchronizedcommunication.

FIG. 4 illustrates an example of a process flow 400 in a system thatsupports synchronization signal periodicity adjustment in accordancewith one or more aspects of the present disclosure. In some examples,process flow 400 may implement aspects of wireless communications system100 and 200. For example, device 405-a, 405-b, and 405-c may be examplesof wireless devices in an IAB network. Accordingly, devices 405 may beexamples of nodes, UEs 115, base stations 105, or like devices asdescribed with reference to FIGS. 1 and 2. Alternative examples of thefollowing may be implemented, where some operations are performed in adifferent order than described or are not performed at all. In somecases, operations may include additional features not mentioned below,or further operations may be added.

At 410, device 405-a may determine a configuration of transmissionperiodicities. The transmission periodicities may include an actualtransmission periodicity and at least one virtual transmissionperiodicity used by device 405-b. At 415, device 405-b may determine aconfiguration of transmission periodicities. Accordingly, thetransmission periodicities may include the actual transmissionperiodicity and the at least one virtual transmission periodicity. Asdescribed herein, the actual transmission periodicity may correspond toa first periodicity of signals, whereas the virtual transmissionperiodicity may correspond to a second periodicity that is shorter than(i.e., more frequent than) the first periodicity. Device 405-a or device405-b may agree upon the timing and frequency of actual periodicitiesand virtual periodicities. This agreement may extend to other devices orUEs 115 in the network. In some examples, the identification of theperiodicities may be made upon setup of the connection between device405-a and device 405-b and may be based on exchange of capabilities ormonitoring requirements between the devices. Additionally oralternatively, there may be a particular configuration supported by bothdevices that is known or predetermined.

At 418, device 405-a and device 405-b may exchange signals to determinelink quality between the devices. For example, the link quality may bedetermined by RSRP, RSRQ, SINR, other measurements, or a combinationthereof. In some cases, at 420, device 405-a may determine a linkcondition of a communication link between device 405-a and device 405-b,which may be based on the signaling at 418. In some cases, similarly, at425, device 405-b may determine a link condition of a communication linkbetween device 405-a and device 405-b.

At 430, device 405-a may select a monitoring periodicity correspondingto the actual transmission periodicity or the at least one virtualtransmission periodicity based on one or more parameters. Similarly, at435, device 405-b may select a transmission periodicity corresponding tothe actual transmission periodicity or the at least one virtualtransmission periodicity based on one or more parameters. In some cases,the one or more parameters include a link condition. In one example,either or both or the devices may determine the link condition is poor,and device 405-a may select a monitoring periodicity corresponding tothe at least one virtual transmission periodicity and device 405-b maytransmission periodicity corresponding to the at least one virtualtransmission periodicity. In such cases, device 405-a and device 405-bmay detect a beam or link failure at similar or different times. Thedetection of the link quality and the adjustment of periodicities may bebased on an error rate, lack of receiving ACKs (or increased receptionof NACKs), measurements performed based on SSBs to determine radio linkfailure, low RSRP, failure to decode a channel due to signal quality,lower than expected SINR or SNR, or the like.

In another example, either or both of the devices may determine that thelink condition is favorable, and the devices may select monitoring andtransmission periodicities corresponding to the actual transmissionperiodicities. The selection of monitoring and transmittingperiodicities may be performed by device 405-a and 405-b in asynchronous manner such that the selection was determined based on bothdevices and occurs at the same time. The selection may also be made inan autonomous manner such that devices perform the selection withoutconsidering the other device, where the selections by the two devicesmay be performed at different times.

At 440, device 405-a may monitor for one or more measurement signalstransmitted by device 405-b, 405-c, or a combination thereof, over thecommunication link in accordance with the selected monitoringperiodicity. For instance, at 445, device 405-b may transmit measurementsignals to device 405-a over the communication link in accordance withthe selected transmission periodicity, where the selected transmissionperiodicity may be based on the current link condition between device405-a and 405-b. In one example, if device 405-a and 405-b were able tosynchronously detect a poor link condition then device 405-a may bemonitoring at a periodicity that matches the transmission periodicity ofdevice 405-b. In another example, device 405-a and 405-b be not becoordinated due to adverse conditions, and device 405-a may bemonitoring at a different periodicity than device 405-b is transmitting.Device 405-b may be transmitting at a periodicity that is less than,matches, or is greater than the periodicity at which device 405-a ismonitoring at.

In some cases, all beams between device 405-a and device 405-b may beblocked resulting in total link failure. In this case, device 405-b mayindicate to other nodes near device 405-b (e.g., device 405-c) toincrease their transmission frequency. In such cases, at 450, device405-c may receive, from device 405-b, an indication to adjust thetransmission periodicity to at least one virtual transmissionperiodicity based on a link condition of a communication link betweendevice 405-a and device 405-b. Device 405-b may transmit this indicationimmediately after switching modes, after a certain number of attempts tocommunicate with device 405-a, or after a certain amount of time afterdetecting poor link quality, or a combination thereof. Device 405-b mayalso signal neighboring nodes if device 405-b does not have thecapability to transmit at a higher frequency. For example, device 405-bmay not have enough resources available to accommodate the highertransmission frequency.

Additionally or alternatively, device 405-b may determine a priority ofdata to be sent to various nodes and devices within the system, anddevice 405-b may determine that the priority of the measurement signalsto device 405-a may be of lower priority. Thus, device 405-b may refrainfrom modifying its transmission periodicity of measurement signals basedon other, higher priority, transmissions. As such, device 405-b maysignal to device 405-c to adjust the transmission periodicity of device405-c. Device 405-b may also include symbol timing information in theadjustment indication 450 to device 405-c. For instance, the symboltiming information may be timing information that corresponds to thesynchronized clocks of device 405-b and device 405-a. In cases where thelink or links between device 405-a and device 405-b fail, there may be aperiod of time before respective clocks at the two device drift out ofsynchronization (e.g., due to the lack of synchronization information orother signaling between the devices). Accordingly, the timinginformation provided by device 405-b to device 405-c may enable device405-c to determine the timing of measurement signals expected by device405-a.

At 455, device 405-c may transmit measurement signals to device 405-a inaccordance with the at least one virtual transmission periodicity. Insome cases, device 405-c may utilize the symbol timing informationprovided by device 405-b to transmit measurement signals during or nearthe symbol time that device 405-a will be monitoring for measurementsignals. In some cases, device 405-a may be able to monitortransmissions from multiple nodes (e.g., device 405-b and device 405-c)and may be able to receive a transmission from device 405-b, device405-c, or a combination thereof. If device 405-a receives a transmissionfrom device 405-c, and does not receive a transmission from device 405-bthen device 405-a may be able to switch to device 405-c that is notbeing blocked. If device 405-a receives a transmission from both device405-b and 405-c then the device 405-a may continue to communicate withdevice 405-b or may switch to device 405-c. Devices such as device 405-cthat may be indicated to switch transmission frequencies and thedifferent transmission rates may be pre-configured or may be determinedon-demand.

FIG. 5 shows a block diagram 500 of a device 505 that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure. The device 505 may be an exampleof aspects of a wireless device, such as a UE 115, base station 105, oraccess node, as described herein. The device 505 may include a receiver510, a communications manager 515, and a transmitter 520. The device 505may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

Receiver 510 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related tosynchronization signal periodicity adjustment). Information may bepassed on to other components of the device 505. The receiver 510 may bean example of aspects of the transceiver 820 or 920 as described withreference to FIGS. 8 and 9. The receiver 510 may utilize a singleantenna or a set of antennas.

The communications manager 515 may determine a configuration of anactual transmission periodicity and at least one virtual transmissionperiodicity used by a second device, select a monitoring periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters, andmonitor for one or more measurement signals transmitted by the seconddevice over a communication link in accordance with the selectedmonitoring periodicity.

The communications manager 515 may also determine a configuration of anactual transmission periodicity and at least one virtual transmissionperiodicity, select a transmission periodicity corresponding to theactual transmission periodicity or the at least one virtual transmissionperiodicity based on one or more parameters, and transmit one or moremeasurement signals to a second device over a communication link inaccordance with the selected transmission periodicity.

The communications manager 515 may also transmit one or more measurementsignals to a first set of one or more devices in accordance with atransmission periodicity, receive, from a second device, an indicationto adjust the transmission periodicity to at least one virtualtransmission periodicity based on one or more parameters of acommunication link between the second device and the one or moredevices, and transmit the one or more measurement signals to a secondset of one or more devices in accordance with the at least one virtualtransmission periodicity. The communications manager 515 may be anexample of aspects of the communications manager 810 or 910 as describedherein.

The communications manager 515, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 515, or itssub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The communications manager 515, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 515, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 515, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an input/output (I/O) component, a transceiver, anetwork server, another computing device, one or more other componentsdescribed in the present disclosure, or a combination thereof inaccordance with various aspects of the present disclosure.

Transmitter 520 may transmit signals generated by other components ofthe device 505. In some examples, the transmitter 520 may be collocatedwith a receiver 510 in a transceiver module. For example, thetransmitter 520 may be an example of aspects of the transceiver 820 or920 as described with reference to FIGS. 8 and 9. The transmitter 520may utilize a single antenna or a set of antennas.

In one or more aspects, the communications manager 515 as describedherein may support improvements in SSB monitoring and transmission. Oneimplementation may allow the device 505 to more flexibly selectdifferent periodicities for signal transmission and correspondingmonitoring of the signal transmissions. For example, the device 505 mayselect different periodicities for signal transmissions andcorresponding monitoring dynamically according to link conditions.

Based on implementing the SSB monitoring and transmissions techniques asdescribed herein, a processor of a UE 115 (e.g., controlling thereceiver 510, the transmitter 520, or the transceiver 820 as describedwith reference to FIG. 8) may increase reliability, mitigate signalingoverhead, and reduce latency in the network because periodicities forsignal transmissions may be flexibly selected.

FIG. 6 shows a block diagram 600 of a device 605 that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure. The device 605 may be an exampleof aspects of a device 505, a UE 115, or a base station 105 as describedherein. The device 605 may include a receiver 610, a communicationsmanager 615, and a transmitter 650. The device 605 may also include aprocessor. Each of these components may be in communication with oneanother (e.g., via one or more buses).

Receiver 610 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related tosynchronization signal periodicity adjustment). Information may bepassed on to other components of the device 605. The receiver 610 may bean example of aspects of the transceiver 820 or 920 as described withreference to FIGS. 8 and 9. The receiver 610 may utilize a singleantenna or a set of antennas.

The communications manager 615 may be an example of aspects of thecommunications manager 515 as described herein. The communicationsmanager 615 may include a configuration manager 620, a link conditionmanager 625, a periodicity manager 630, a monitoring component 635, asignal manager 640, and an indication manager 645. The communicationsmanager 615 may be an example of aspects of the communications manager810 or 910 as described herein.

The configuration manager 620 may determine a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity used by a second device. The configuration manager 620 maydetermine a configuration of an actual transmission periodicity and atleast one virtual transmission periodicity.

In some cases, the link condition manager 625 may determine a linkcondition of a communication link between the first device and thesecond device. The link condition manager 625 may determine a linkcondition of a communication link between the first device and a seconddevice.

The periodicity manager 630 may select a monitoring periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters. Theperiodicity manager 630 may select a transmission periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters. Insome cases, the one or more parameters may include a link condition. Themonitoring component 635 may monitor for one or more measurement signalstransmitted by the second device over a communication link in accordancewith the selected monitoring periodicity.

The signal manager 640 may transmit one or more measurement signals tothe second device over the communication link in accordance with theselected transmission periodicity. The indication manager 645 mayreceive, from a second device, an indication to adjust the transmissionperiodicity to at least one virtual transmission periodicity based onone or more parameters of a communication link between the second deviceand a second set of one or more devices. The signal manager 640 maytransmit one or more measurement signals to a first set of one or moredevices in accordance with a transmission periodicity and transmit theone or more measurement signals to the second set of one or more devicesin accordance with the at least one virtual transmission periodicity.

Transmitter 650 may transmit signals generated by other components ofthe device 605. In some examples, the transmitter 650 may be collocatedwith a receiver 610 in a transceiver module. For example, thetransmitter 650 may be an example of aspects of the transceiver 820 or920 as described with reference to FIGS. 8 and 9. The transmitter 650may utilize a single antenna or a set of antennas.

FIG. 7 shows a block diagram 700 of a communications manager 705 thatsupports synchronization signal periodicity adjustment in accordancewith one or more aspects of the present disclosure. The communicationsmanager 705 may be an example of aspects of a communications manager515, a communications manager 615, or a communications manager 810described herein. The communications manager 705 may include aconfiguration manager 710, a link condition manager 715, a periodicitymanager 720, a monitoring component 725, a timing component 730, aconnection manager 735, a signal manager 740, an indication manager 745,and a mode manager 750. Each of these modules may communicate, directlyor indirectly, with one another (e.g., via one or more buses).

The configuration manager 710 may determine a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity used by a second device. In some cases, the link conditionmanager 715 may determine a link condition of a communication linkbetween the first device and the second device. The periodicity manager720 may select a monitoring periodicity corresponding to the actualtransmission periodicity or the at least one virtual transmissionperiodicity based on one or more parameters. In some cases, the one ormore parameters include a link condition. The monitoring component 725may monitor for one or more measurement signals transmitted by thesecond device over the communication link in accordance with theselected monitoring periodicity.

In some examples, the periodicity manager 720 may select the monitoringperiodicity to correspond to the actual transmission periodicity. Insome examples, the link condition manager 715 may determine that thelink condition satisfies a threshold. In some examples, the periodicitymanager 720 may adjust the monitoring periodicity to correspond to theat least one virtual transmission periodicity based on the linkcondition satisfying the threshold, the at least one virtualtransmission periodicity being shorter than the actual transmissionperiodicity.

In some examples, the link condition manager 715 may determine that thelink condition satisfies a second threshold. In some examples, theperiodicity manager 720 may adjust the monitoring periodicity tocorrespond to the actual transmission periodicity based on the linkcondition satisfying the second threshold.

In some examples, the link condition manager 715 may determine that thecommunication link has failed based on the link condition. Theconnection manager 735 may establish a connection with one or more otherdevices based on the failed communication link. In some examples, thesignal manager 740 may receive the one or more measurement signals fromthe one or more other devices.

In some examples, the indication manager 745 may receive an indicationthat the second device is transmitting the one or more measurementsignals in accordance with the at least one virtual transmissionperiodicity. In some examples, the periodicity manager 720 may selectthe monitoring periodicity to correspond to the at least one virtualtransmission periodicity based on the indication.

In some examples, the periodicity manager 720 may select the monitoringperiodicity to correspond to the at least one virtual transmissionperiodicity based on the link condition. In some examples, theindication manager 745 may transmit, to the second device, an indicationthat the monitoring periodicity corresponds to the at least one virtualtransmission periodicity.

The mode manager 750 may operate in a first monitoring mode associatedwith the actual transmission periodicity. In some examples, the modemanager 750 may operate in a second monitoring mode associated with theat least one virtual transmission periodicity.

In some examples, the indication manager 745 may receive an indicationof the configuration via RRC signaling. In some examples, the signalmanager 740 may receive the one or more measurement signals from thesecond device based on the monitoring. In some cases, the one or moremeasurement signals include SSBs, or CSI-RSs, or SRSs, or a combinationthereof.

In some cases, the link condition includes an error rate for informationtransmitted over the communication link. In some cases, thecommunication link includes one or more directional beams operating overa mmW radio frequency spectrum band. In some cases, the first deviceincludes a first node in an IAB network, and the second device includesa second node in the IAB network.

In some examples, the configuration manager 710 may determine aconfiguration of an actual transmission periodicity and at least onevirtual transmission periodicity. In some examples, the link conditionmanager 715 may determine a link condition of a communication linkbetween the first device and a second device. In some examples, theperiodicity manager 720 may select a transmission periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters. Insome cases, the one or more parameters include a link condition. Thesignal manager 740 may transmit one or more measurement signals to asecond device over the communication link in accordance with theselected transmission periodicity.

In some examples, the periodicity manager 720 may select thetransmission periodicity to correspond to the actual transmissionperiodicity. In some examples, the link condition manager 715 maydetermine that the link condition satisfies a threshold. In someexamples, the periodicity manager 720 may adjust the transmissionperiodicity to correspond to the at least one virtual transmissionperiodicity based on the link condition satisfying the threshold, the atleast one virtual transmission periodicity being shorter than the actualtransmission periodicity.

The timing component 730 may start a timer based on adjusting themonitoring periodicity to correspond to the at least one virtualtransmission periodicity. In some examples, the timing component 730 maydetermine that the timer has expired. In some examples, the indicationmanager 745 may transmit, to one or more other devices, an indication totransmit the one or more measurement signals in accordance with the atleast one virtual transmission periodicity.

In some examples, the link condition manager 715 may determine that thelink condition satisfies a second threshold. In some examples, theperiodicity manager 720 may adjust the transmission periodicity tocorrespond to the actual transmission periodicity based on the linkcondition satisfying the second threshold.

In some cases, the indication manager 745 may transmit, to one or moreother devices, symbol timing information for transmitting the one ormore measurement signals.

In some examples, the periodicity manager 720 may select thetransmission periodicity to correspond to the at least one virtualtransmission periodicity based on the link condition. In some examples,the indication manager 745 may transmit, to the second device, anindication that the transmission periodicity corresponds to the at leastone virtual transmission periodicity.

In some examples, the indication manager 745 may receive an indicationthat the second device is monitoring for the one or more measurementsignals in accordance with the at least one virtual transmissionperiodicity. In some examples, the periodicity manager 720 may selectthe transmission periodicity to correspond to the at least one virtualtransmission periodicity based on the indication.

In some examples, the mode manager 750 may operate in a firsttransmission mode associated with the actual transmission periodicity.In some examples, the mode manager 750 may operate in a secondtransmission mode associated with the at least one virtual transmissionperiodicity. In some examples, the indication manager 745 may transmitan indication of the configuration via RRC signaling. In some examples,the monitoring component 725 may monitor for the one or more measurementsignals transmitted from one or more other devices based on the timerexpiring.

In some examples, the timing component 730 may start a timer based onadjusting the transmission periodicity to correspond to the at least onevirtual transmission periodicity. In some examples, the timing component730 may determine that the timer has expired. In some examples, theindication manager 745 may transmit, to one or more other devices, anindication to transmit the one or more measurement signals in accordancewith the at least one virtual transmission periodicity based on the linkcondition.

In some examples, the signal manager 740 may transmit one or moremeasurement signals to a first set of one or more devices in accordancewith a transmission periodicity. The indication manager 745 may receive,from a second device, an indication to adjust the transmissionperiodicity to at least one virtual transmission periodicity based onone or more parameters of a communication link between the second deviceand a second set of one or more devices. In some cases, the one or moreparameters include a link condition.

In some examples, the signal manager 740 may transmit the one or moremeasurement signals to the second set of one or more devices inaccordance with the at least one virtual transmission periodicity.

In some examples, the configuration manager 710 may receive aconfiguration of at least one virtual transmission periodicity used bythe second device, the configuration being received prior to theindication from the second device, where the at least one virtualtransmission periodicity is a based on the configuration. In someexamples, the configuration manager 710 may determine a configuration ofthe at least one virtual transmission periodicity.

Additionally or alternatively, the indication manager 745 may receive,from a second device, symbol timing information and transmit the one ormore measurement signals to the second set of one or more devices basedon the symbol timing information.

In some cases, the at least one virtual transmission periodicity isshorter than the transmission periodicity. In some cases, the firstdevice includes a first node in an IAB network, and the second deviceincludes a second node in the IAB network.

FIG. 8 shows a diagram of a system 800 including a device 805 thatsupports synchronization signal periodicity adjustment in accordancewith one or more aspects of the present disclosure. The device 805 maybe an example of or include the components of device 505, device 605, ora UE 115 as described herein. The device 805 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a communicationsmanager 810, a transceiver 820, an antenna 825, memory 830, a processor840, and an I/O controller 850. These components may be in electroniccommunication via one or more buses (e.g., bus 855).

The communications manager 810 may determine a configuration of anactual transmission periodicity and at least one virtual transmissionperiodicity used by a second device, select a monitoring periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters, andmonitor for one or more measurement signals transmitted by the seconddevice over a communication link in accordance with the selectedmonitoring periodicity.

The communications manager 810 may also determine a configuration of anactual transmission periodicity and at least one virtual transmissionperiodicity, select a transmission periodicity corresponding to theactual transmission periodicity or the at least one virtual transmissionperiodicity based on one or more parameters, and transmit one or moremeasurement signals to a second device over a communication link inaccordance with the selected transmission periodicity.

The communications manager 810 may also transmit one or more measurementsignals to a first set of one or more devices in accordance with atransmission periodicity receive, from a second device, an indication toadjust the transmission periodicity to at least one virtual transmissionperiodicity based on one or more parameters of a communication linkbetween the second device and a second set of one or more devices, andtransmit the one or more measurement signals to the second set of one ormore wireless devices in accordance with the at least one virtualtransmission periodicity.

Transceiver 820 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 820 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 820may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas. In some cases, the wireless devicemay include a single antenna 825. However, in some cases, the device mayhave more than one antenna 825, which may be capable of concurrentlytransmitting or receiving multiple wireless transmissions.

The memory 830 may include random-access memory (RAM), read-only memory(ROM), or a combination thereof. The memory 830 may storecomputer-readable code 835 including instructions that, when executed bya processor (e.g., the processor 840) cause the device to performvarious functions described herein. In some cases, the memory 830 maycontain, among other things, a basic input/output system (BIOS) whichmay control basic hardware or software operation such as the interactionwith peripheral components or devices.

The processor 840 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 840 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 840. The processor 840 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 830) to cause the device 805 to perform variousfunctions (e.g., functions or tasks supporting synchronization signalperiodicity adjustment).

The I/O controller 850 may manage input and output signals for thedevice 805. The I/O controller 850 may also manage peripherals notintegrated into the device 805. In some cases, the I/O controller 850may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 850 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 850may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 850may be implemented as part of a processor. In some cases, a user mayinteract with the device 805 via the I/O controller 850 or via hardwarecomponents controlled by the I/O controller 850.

The code 835 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 835 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 835 may not be directly executable by theprocessor 840 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 9 shows a diagram of a system 900 including a device 905 thatsupports synchronization signal periodicity adjustment in accordancewith one or more aspects of the present disclosure. The device 905 maybe an example of or include the components of device 505, device 605, ora base station 105 as described herein. The device 905 may includecomponents for bi-directional voice and data communications includingcomponents for transmitting and receiving communications, including acommunications manager 910, a network communications manager 915, atransceiver 920, an antenna 925, memory 930, a processor 940, and aninter-station communications manager 945. These components may be inelectronic communication via one or more buses (e.g., bus 955).

The communications manager 910 may determine a configuration of anactual transmission periodicity and at least one virtual transmissionperiodicity used by a second device, select a monitoring periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based on one or more parameters, andmonitor for one or more measurement signals transmitted by the seconddevice over a communication link in accordance with the selectedmonitoring periodicity.

The communications manager 910 may also determine a configuration of anactual transmission periodicity and at least one virtual transmissionperiodicity, select a transmission periodicity corresponding to theactual transmission periodicity or the at least one virtual transmissionperiodicity based on one or more parameters, and transmit one or moremeasurement signals to a second device over a communication link inaccordance with the selected transmission periodicity.

The communications manager 910 may also transmit one or more measurementsignals to a first set of one or more devices in accordance with atransmission periodicity, receive, from a second device, an indicationto adjust the transmission periodicity to at least one virtualtransmission periodicity based on one or more parameters of acommunication link between the second device and a second set of one ormore devices, and transmit the one or more measurement signals to thesecond set of one or more devices in accordance with the at least onevirtual transmission periodicity.

Network communications manager 915 may manage communications with thecore network (e.g., via one or more wired backhaul links). For example,the network communications manager 915 may manage the transfer of datacommunications for client devices, such as one or more UEs 115.

Transceiver 920 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 920 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 920may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas. In some cases, the wireless devicemay include a single antenna 925. However, in some cases the device mayhave more than one antenna 925, which may be capable of concurrentlytransmitting or receiving multiple wireless transmissions.

The memory 930 may include RAM, ROM, or a combination thereof. Thememory 930 may store computer-readable code 935 including instructionsthat, when executed by a processor (e.g., the processor 940) cause thedevice to perform various functions described herein. In some cases, thememory 930 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 940 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 940 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 940. The processor 940 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 930) to cause the device 905 to perform variousfunctions (e.g., functions or tasks supporting synchronization signalperiodicity adjustment).

Inter-station communications manager 945 may manage communications withother base station 105, and may include a controller or scheduler forcontrolling communications with UEs 115 in cooperation with other basestations 105. For example, the inter-station communications manager 945may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, inter-station communications manager 945may provide an X2 interface within an LTE/LTE-A wireless communicationnetwork technology to provide communication between base stations 105.

The code 935 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 935 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 935 may not be directly executable by theprocessor 940 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 10 shows a flowchart illustrating a method 1000 that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure. The operations of method 1000may be implemented by a device (e.g., a wireless device), such as a UE115 or base station 105, or its components as described herein. Forexample, the operations of method 1000 may be performed by acommunications manager as described with reference to FIGS. 5 through 9.In some examples, a device may execute a set of instructions to controlthe functional elements of the device to perform the functions describedherein. Additionally or alternatively, a device may perform aspects ofthe functions described herein using special-purpose hardware.

At 1005, the device may determine a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity used by a second device. The operations of 1005 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1005 may be performed by a configurationmanager as described with reference to FIGS. 5 through 9.

At 1010, the device may select a monitoring periodicity corresponding tothe actual transmission periodicity or the at least one virtualtransmission periodicity based on one or more parameters. The operationsof 1010 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1010 may be performed by aperiodicity manager as described with reference to FIGS. 5 through 9.

At 1015, the device may monitor for one or more measurement signalstransmitted by the second device over a communication link in accordancewith the selected monitoring periodicity. The operations of 1015 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1015 may be performed by a monitoringcomponent as described with reference to FIGS. 5 through 9.

FIG. 11 shows a flowchart illustrating a method 1100 that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure. The operations of method 1100may be implemented by a device (e.g., a wireless device), such as a UE115 or base station 105, or its components as described herein. Forexample, the operations of method 1100 may be performed by acommunications manager as described with reference to FIGS. 5 through 9.In some examples, a device may execute a set of instructions to controlthe functional elements of the device to perform the functions describedherein. Additionally or alternatively, a device may perform aspects ofthe functions described herein using special-purpose hardware.

At 1105, the device may determine a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity used by a second device. The operations of 1105 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1105 may be performed by a configurationmanager as described with reference to FIGS. 5 through 9.

At 1110, the device may determine a link condition of a communicationlink between the first device and the second device. The operations of1110 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1110 may be performed by a linkcondition manager as described with reference to FIGS. 5 through 9.

At 1115, the device may select the monitoring periodicity to correspondto the actual transmission periodicity. The operations of 1115 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1115 may be performed by a periodicitymanager as described with reference to FIGS. 5 through 9.

At 1120, the device may monitor for one or more measurement signalstransmitted by the second device over the communication link inaccordance with the selected monitoring periodicity. The operations of1120 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1120 may be performed by amonitoring component as described with reference to FIGS. 5 through 9.

At 1125, the device may determine that the link condition satisfies athreshold. The operations of 1125 may be performed according to themethods described herein. In some examples, aspects of the operations of1125 may be performed by a link condition manager as described withreference to FIGS. 5 through 9.

At 1130, the device may adjust the monitoring periodicity to correspondto the at least one virtual transmission periodicity based on the linkcondition satisfying the threshold, the at least one virtualtransmission periodicity being shorter than the actual transmissionperiodicity. The operations of 1130 may be performed according to themethods described herein. In some examples, aspects of the operations of1130 may be performed by a periodicity manager as described withreference to FIGS. 5 through 9.

FIG. 12 shows a flowchart illustrating a method 1200 that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure. The operations of method 1200may be implemented by a device (e.g., a wireless device), such as a UE115 or base station 105, or its components as described herein. Forexample, the operations of method 1200 may be performed by acommunications manager as described with reference to FIGS. 5 through 9.In some examples, a device may execute a set of instructions to controlthe functional elements of the device to perform the functions describedherein. Additionally or alternatively, a device may perform aspects ofthe functions described herein using special-purpose hardware.

At 1205, the device may determine a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity used by a second device. The operations of 1205 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1205 may be performed by a configurationmanager as described with reference to FIGS. 5 through 9.

At 1210, the device may determine a link condition of a communicationlink between the first device and the second device. The operations of1210 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1210 may be performed by a linkcondition manager as described with reference to FIGS. 5 through 9.

At 1215, the device may select a monitoring periodicity corresponding tothe actual transmission periodicity or the at least one virtualtransmission periodicity based on the link condition. The operations of1215 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1215 may be performed by aperiodicity manager as described with reference to FIGS. 5 through 9.

At 1220, the device may monitor for one or more measurement signalstransmitted by the second device over the communication link inaccordance with the selected monitoring periodicity. The operations of1220 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1220 may be performed by amonitoring component as described with reference to FIGS. 5 through 9.

At 1225, the device may determine that the communication link has failedbased on the link condition. The operations of 1225 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1225 may be performed by a link condition manager asdescribed with reference to FIGS. 5 through 9.

At 1230, the device may establish a connection with one or more otherdevices based on the failed communication link. The operations of 1230may be performed according to the methods described herein. In someexamples, aspects of the operations of 1230 may be performed by aconnection manager as described with reference to FIGS. 5 through 9.

At 1235, the device may receive the one or more measurement signals fromthe one or more other devices. The operations of 1235 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1235 may be performed by a signal manager as describedwith reference to FIGS. 5 through 9.

FIG. 13 shows a flowchart illustrating a method 1300 that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure. The operations of method 1300may be implemented by a device (e.g., a wireless device), such as a UE115 or base station 105, or its components as described herein. Forexample, the operations of method 1300 may be performed by acommunications manager as described with reference to FIGS. 5 through 9.In some examples, a device may execute a set of instructions to controlthe functional elements of the device to perform the functions describedherein. Additionally or alternatively, a device may perform aspects ofthe functions described herein using special-purpose hardware.

At 1305, the device may determine a configuration of an actualtransmission periodicity and at least one virtual transmissionperiodicity. The operations of 1305 may be performed according to themethods described herein. In some examples, aspects of the operations of1305 may be performed by a configuration manager as described withreference to FIGS. 5 through 9.

At 1310, the device may select a transmission periodicity correspondingto the actual transmission periodicity or the at least one virtualtransmission periodicity based on one or more parameters. The operationsof 1310 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1310 may be performed by aperiodicity manager as described with reference to FIGS. 5 through 9.

At 1315, the device may transmit one or more measurement signals to asecond device over a communication link in accordance with the selectedtransmission periodicity. The operations of 1315 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1315 may be performed by a signal manager as describedwith reference to FIGS. 5 through 9.

FIG. 14 shows a flowchart illustrating a method 1400 that supportssynchronization signal periodicity adjustment in accordance with one ormore aspects of the present disclosure. The operations of method 1400may be implemented by a device (e.g., a wireless device), such as a UE115 or base station 105, or its components as described herein. Forexample, the operations of method 1400 may be performed by acommunications manager as described with reference to FIGS. 5 through 9.In some examples, a device may execute a set of instructions to controlthe functional elements of the device to perform the functions describedherein. Additionally or alternatively, a device may perform aspects ofthe functions described herein using special-purpose hardware.

At 1405, the device may transmit one or more measurement signals to afirst set of one or more wireless devices in accordance with atransmission periodicity. The operations of 1405 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1405 may be performed by a signal manager as describedwith reference to FIGS. 5 through 9.

At 1410, the device may receive, from a second device, an indication toadjust the transmission periodicity to at least one virtual transmissionperiodicity based on one or more parameters of a communication linkbetween the second device and a second set of one or more devices. Theoperations of 1410 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1410 may beperformed by an indication manager as described with reference to FIGS.5 through 9.

At 1415, the device may transmit the one or more measurement signals tothe second set of one or more devices in accordance with the at leastone virtual transmission periodicity. The operations of 1415 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1415 may be performed by a signal manageras described with reference to FIGS. 5 through 9.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Example 1

A method for communications at a first device, comprising: determining aconfiguration of an actual transmission periodicity and at least onevirtual transmission periodicity used by a second device; selecting amonitoring periodicity corresponding to the actual transmissionperiodicity or the at least one virtual transmission periodicity basedat least in part on one or more parameters; and monitoring for one ormore measurement signals transmitted by the second device over acommunication link in accordance with the selected monitoringperiodicity.

Example 2

The method of example 1, wherein the one or more parameters comprise alink condition.

Example 3

The method of example 2, wherein the link condition comprises an errorrate for information transmitted over the communication link.

Example 4

The method of any of examples 1 to 3, further comprising: determining alink condition of the communication link between the first device andthe second device.

Example 5

The method of any of examples 1 to 5, further comprising: selecting themonitoring periodicity to correspond to the actual transmissionperiodicity; determining that a link condition satisfies a threshold;and adjusting the monitoring periodicity to correspond to the at leastone virtual transmission periodicity based at least in part on the linkcondition satisfying the threshold, the at least one virtualtransmission periodicity being shorter than the actual transmissionperiodicity.

Example 6

The method of example 5, further comprising: starting a timer based atleast in part on adjusting the monitoring periodicity to correspond tothe at least one virtual transmission periodicity; determining that thetimer has expired; and monitoring for the one or more measurementsignals transmitted from one or more other devices based at least inpart on the timer expiring.

Example 7

The method of any of examples 5 or 6, further comprising: determiningthat the link condition satisfies a second threshold; and adjusting themonitoring periodicity to correspond to the actual transmissionperiodicity based at least in part on the link condition satisfying thesecond threshold.

Example 8

The method of any of examples 1 to 7, further comprising: determiningthat the communication link has failed based at least in part on a linkcondition; establishing a connection with one or more other devicesbased at least in part on the failed communication link; and receivingthe one or more measurement signals from the one or more other devices.

Example 9

The method of any of examples 1 to 8, further comprising: receiving anindication that the second device is transmitting the one or moremeasurement signals in accordance with the at least one virtualtransmission periodicity; and selecting the monitoring periodicity tocorrespond to the at least one virtual transmission periodicity based atleast in part on the indication.

Example 10

The method of any of examples 1 to 10, further comprising: selecting themonitoring periodicity to correspond to the at least one virtualtransmission periodicity based at least in part on a link condition; andtransmitting, to the second device, an indication that the monitoringperiodicity corresponds to the at least one virtual transmissionperiodicity.

Example 11

The method of any of examples 1 to 10, further comprising: operating ina first monitoring mode associated with the actual transmissionperiodicity.

Example 12

The method of any of examples 1 to 11, further comprising: operating ina second monitoring mode associated with the at least one virtualtransmission periodicity.

Example 13

The method of any of examples 1 to 12, wherein determining theconfiguration of the actual transmission periodicity and the at leastone virtual transmission periodicity comprises: receiving an indicationof the configuration via RRC signaling.

Example 14

The method of any of examples 1 to 13, further comprising: receiving theone or more measurement signals from the second device based at least inpart on the monitoring.

Example 15

The method of any of examples 1 to 14, wherein the one or moremeasurement signals comprise SSBs, or CSI-RSs, or SRSs, or a combinationthereof

Example 16

The method of any of examples 1 to 15, wherein the first devicecomprises a first node in an IAB network and the second device comprisesa second node in the IAB network.

Example 17

The method of any of examples 1 to 16, wherein the communication linkcomprises one or more directional beams operating over a mmW radiofrequency spectrum band.

Example 18

An apparatus comprising at least one means for performing a method ofany of examples 1 to 17.

Example 19

An apparatus for wireless communications comprising a processor; andmemory coupled to the processor, the processor and memory configured toperform a method of any of examples 1 to 17.

Example 20

A non-transitory computer-readable medium storing code for wirelesscommunications, the code comprising instructions executable by aprocessor to perform a method of any of examples 1 to 17.Example 21: Amethod for communications at a first device, comprising: determining aconfiguration of an actual transmission periodicity and at least onevirtual transmission periodicity; selecting a transmission periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based at least in part on one or moreparameters; and transmitting one or more measurement signals to a seconddevice over a communication link in accordance with the selectedtransmission periodicity.

Example 22

The method of example 21, wherein the one or more parameters comprise alink condition.

Example 23

The method of any of examples 21 or 22, further comprising: determininga link condition of a communication link between the first device andthe second device.

Example 24

The method of any of examples 21 to 23, further comprising: selectingthe transmission periodicity to correspond to the actual transmissionperiodicity; determining that a link condition satisfies a threshold;and adjusting the transmission periodicity to correspond to the at leastone virtual transmission periodicity based at least in part on the linkcondition satisfying the threshold, the at least one virtualtransmission periodicity being shorter than the actual transmissionperiodicity.

Example 25

The method of example 24, further comprising: starting a timer based atleast in part on adjusting the transmission periodicity to correspond tothe at least one virtual transmission periodicity; determining that thetimer has expired; and transmitting, to one or more other devices, anindication to transmit the one or more measurement signals in accordancewith the at least one virtual transmission periodicity.

Example 26

The method of any of examples 24 or 25, further comprising: determiningthat the link condition satisfies a second threshold; and adjusting thetransmission periodicity to correspond to the actual transmissionperiodicity based at least in part on the link condition satisfying thesecond threshold.

Example 27

The method of any of examples 21 to 26, further comprising:transmitting, to one or more other devices, an indication to transmitthe one or more measurement signals in accordance with the at least onevirtual transmission periodicity based at least in part on a linkcondition.

Example 28

The method of any of examples 21 to 27, further comprising:transmitting, to one or more other devices, symbol timing informationfor transmitting the one or more measurement signals.

Example 29

The method of any of examples 21 to 28, further comprising: selectingthe transmission periodicity to correspond to the at least one virtualtransmission periodicity based at least in part on a link condition; andtransmitting, to the second device, an indication that the transmissionperiodicity corresponds to the at least one virtual transmissionperiodicity.

Example 30

The method of any of examples 21 to 29, further comprising: receiving anindication that the second device is monitoring for the one or moremeasurement signals in accordance with the at least one virtualtransmission periodicity; and selecting the transmission periodicity tocorrespond to the at least one virtual transmission periodicity based atleast in part on the indication.

Example 31

The method of any of examples 21 to 30, further comprising: operating ina first transmission mode associated with the actual transmissionperiodicity.

Example 32

The method of any of examples 21 to 31, further comprising: operating ina second transmission mode associated with the at least one virtualtransmission periodicity.

Example 33

The method of any of examples 21 to 32, wherein transmitting theconfiguration of the actual transmission periodicity and the at leastone virtual transmission periodicity comprises: transmitting anindication of the configuration via RRC signaling.

Example 34

An apparatus comprising at least one means for performing a method ofany of examples 21 to 33.

Example 35

An apparatus for wireless communications comprising a processor; andmemory coupled to the processor, the processor and memory configured toperform a method of any of examples 21 to 33.

Example 36

A non-transitory computer-readable medium storing code for wirelesscommunications, the code comprising instructions executable by aprocessor to perform a method of any of examples 21 to 33.

Example 37

A method for communications at a first device, comprising: transmittingone or more measurement signals to a first set of one or more devices inaccordance with a transmission periodicity; receiving, from a seconddevice, an indication to adjust the transmission periodicity to at leastone virtual transmission periodicity based at least in part on one ormore parameters of a communication link between the second device and asecond set of one or more devices; and transmitting the one or moremeasurement signals to the second set of one or more devices inaccordance with the at least one virtual transmission periodicity.

Example 38

The method of example 37, wherein the one or more parameters comprise alink condition.

Example 39

The method of any of examples 37 or 38, further comprising: receiving aconfiguration of at least one virtual transmission periodicity used bythe second device, the configuration being received prior to theindication from the second device, wherein the at least one virtualtransmission periodicity is a based at least in part on theconfiguration.

Example 40

The method of any of examples 37 to 39, further comprising: determininga configuration of the at least one virtual transmission periodicity.

Example 41

The method of any of examples 37 to 40, further comprising: receiving,from a second device, symbol timing information; and transmitting theone or more measurement signals to the second set of one or more devicesbased at least in part on the symbol timing information.

Example 42

The method of any of examples 37 to 41, wherein the at least one virtualtransmission periodicity is shorter than the transmission periodicity.

Example 43

The method of any of examples 37 to 42, wherein the first wirelessdevice comprises a first node in an IAB network and the second wirelessdevice comprises a second node in the IAB network.

Example 44

An apparatus comprising at least one means for performing a method ofany of examples 37 to 43.

Example 45

An apparatus for wireless communications comprising a processor; andmemory coupled to the processor, the processor and memory configured toperform a method of any of examples 37 to 43.

Example 46

A non-transitory computer-readable medium storing code for wirelesscommunications, the code comprising instructions executable by aprocessor to perform a method of any of examples 37 to 43.

Techniques described herein may be used for various wirelesscommunications systems such as CDMA, TDMA, FDMA, OFDMA, single carrierfrequency division multiple access (SC-FDMA), and other systems. A CDMAsystem may implement a radio technology such as CDMA2000, UniversalTerrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95,and IS-856 standards. IS-2000 Releases may be commonly referred to asCDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned herein as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell maybe associated with a lower-powered base station, as compared with amacro cell, and a small cell may operate in the same or different (e.g.,licensed, unlicensed) frequency bands as macro cells. Small cells mayinclude pico cells, femto cells, and micro cells according to variousexamples. A pico cell, for example, may cover a small geographic areaand may allow unrestricted access by UEs with service subscriptions withthe network provider. A femto cell may also cover a small geographicarea (e.g., a home) and may provide restricted access by UEs having anassociation with the femto cell (e.g., UEs in a closed subscriber group(CSG), UEs for users in the home, and the like). An eNB for a macro cellmay be referred to as a macro eNB. An eNB for a small cell may bereferred to as a small cell eNB, a pico eNB, a femto eNB, or a home eNB.An eNB may support one or multiple (e.g., two, three, four, and thelike) cells, and may also support communications using one or multiplecomponent carriers.

The wireless communications systems described herein may supportsynchronous or asynchronous operation. For synchronous operation, thebase stations may have similar frame timing, and transmissions fromdifferent base stations may be approximately aligned in time. Forasynchronous operation, the base stations may have different frametiming, and transmissions from different base stations may not bealigned in time. The techniques described herein may be used for eithersynchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA, or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for communications at a first device,comprising: determining a configuration of an actual transmissionperiodicity and at least one virtual transmission periodicity used by asecond device; selecting a monitoring periodicity corresponding to theactual transmission periodicity or the at least one virtual transmissionperiodicity based at least in part on one or more parameters; andmonitoring for one or more measurement signals transmitted by the seconddevice over a communication link in accordance with the selectedmonitoring periodicity.
 2. The method of claim 1, wherein the one ormore parameters comprise a link condition.
 3. The method of claim 2,wherein the link condition comprises an error rate for informationtransmitted over the communication link.
 4. The method of claim 1,further comprising: determining a link condition of the communicationlink between the first device and the second device.
 5. The method ofclaim 1, further comprising: selecting the monitoring periodicity tocorrespond to the actual transmission periodicity; determining that alink condition satisfies a threshold; and adjusting the monitoringperiodicity to correspond to the at least one virtual transmissionperiodicity based at least in part on the link condition satisfying thethreshold, the at least one virtual transmission periodicity beingshorter than the actual transmission periodicity.
 6. The method of claim5, further comprising: starting a timer based at least in part onadjusting the monitoring periodicity to correspond to the at least onevirtual transmission periodicity; determining that the timer hasexpired; and monitoring for the one or more measurement signalstransmitted from one or more other devices based at least in part on thetimer expiring.
 7. The method of claim 5, further comprising:determining that the link condition satisfies a second threshold; andadjusting the monitoring periodicity to correspond to the actualtransmission periodicity based at least in part on the link conditionsatisfying the second threshold.
 8. The method of claim 1, furthercomprising: determining that the communication link has failed based atleast in part on a link condition; establishing a connection with one ormore other devices based at least in part on the failed communicationlink; and receiving the one or more measurement signals from the one ormore other devices.
 9. The method of claim 1, further comprising:receiving an indication that the second device is transmitting the oneor more measurement signals in accordance with the at least one virtualtransmission periodicity; and selecting the monitoring periodicity tocorrespond to the at least one virtual transmission periodicity based atleast in part on the indication.
 10. The method of claim 1, furthercomprising: selecting the monitoring periodicity to correspond to the atleast one virtual transmission periodicity based at least in part on alink condition; and transmitting, to the second device, an indicationthat the monitoring periodicity corresponds to the at least one virtualtransmission periodicity.
 11. The method of claim 1, further comprising:operating in a first monitoring mode associated with the actualtransmission periodicity; and operating in a second monitoring modeassociated with the at least one virtual transmission periodicity. 12.The method of claim 1, wherein determining the configuration of theactual transmission periodicity and the at least one virtualtransmission periodicity comprises: receiving an indication of theconfiguration via radio resource control signaling.
 13. A method forcommunications at a first device, comprising: determining aconfiguration of an actual transmission periodicity and at least onevirtual transmission periodicity; selecting a transmission periodicitycorresponding to the actual transmission periodicity or the at least onevirtual transmission periodicity based at least in part on one or moreparameters; and transmitting one or more measurement signals to a seconddevice over a communication link in accordance with the selectedtransmission periodicity.
 14. The method of claim 13, wherein the one ormore parameters comprise a link condition.
 15. The method of claim 13,further comprising: determining a link condition of the communicationlink between the first device and the second device.
 16. The method ofclaim 13, further comprising: selecting the transmission periodicity tocorrespond to the actual transmission periodicity; determining that alink condition satisfies a threshold; and adjusting the transmissionperiodicity to correspond to the at least one virtual transmissionperiodicity based at least in part on the link condition satisfying thethreshold, the at least one virtual transmission periodicity beingshorter than the actual transmission periodicity.
 17. The method ofclaim 16, further comprising: starting a timer based at least in part onadjusting the transmission periodicity to correspond to the at least onevirtual transmission periodicity; determining that the timer hasexpired; and transmitting, to one or more other devices, an indicationto transmit the one or more measurement signals in accordance with theat least one virtual transmission periodicity.
 18. The method of claim16, further comprising: determining that the link condition satisfies asecond threshold; and adjusting the transmission periodicity tocorrespond to the actual transmission periodicity based at least in parton the link condition satisfying the second threshold.
 19. The method ofclaim 13, further comprising: transmitting, to one or more otherdevices, an indication to transmit the one or more measurement signalsin accordance with the at least one virtual transmission periodicitybased at least in part on a link condition.
 20. The method of claim 13,further comprising: transmitting, to one or more other devices, symboltiming information for transmitting the one or more measurement signals.21. The method of claim 13, further comprising: selecting thetransmission periodicity to correspond to the at least one virtualtransmission periodicity based at least in part on a link condition; andtransmitting, to the second device, an indication that the transmissionperiodicity corresponds to the at least one virtual transmissionperiodicity.
 22. The method of claim 13, further comprising: receivingan indication that the second device is monitoring for the one or moremeasurement signals in accordance with the at least one virtualtransmission periodicity; and selecting the transmission periodicity tocorrespond to the at least one virtual transmission periodicity based atleast in part on the indication.
 23. The method of claim 13, furthercomprising: operating in a first transmission mode associated with theactual transmission periodicity; and operating in a second transmissionmode associated with the at least one virtual transmission periodicity.24. A method for communications at a first device, comprising:transmitting one or more measurement signals to a first set of one ormore devices in accordance with a transmission periodicity; receiving,from a second device, an indication to adjust the transmissionperiodicity to at least one virtual transmission periodicity based atleast in part on one or more parameters of a communication link betweenthe second device and a second set of one or more devices; andtransmitting the one or more measurement signals to the second set ofone or more devices in accordance with the at least one virtualtransmission periodicity.
 25. The method of claim 24, wherein the one ormore parameters comprise a link condition.
 26. The method of claim 24,further comprising: receiving a configuration of at least one virtualtransmission periodicity used by the second device, the configurationbeing received prior to the indication from the second device, whereinthe at least one virtual transmission periodicity is a based at least inpart on the configuration.
 27. The method of claim 24, furthercomprising: determining a configuration of the at least one virtualtransmission periodicity.
 28. The method of claim 24, furthercomprising: receiving, from a second device, symbol timing information;and transmitting the one or more measurement signals to the second setof one or more devices based at least in part on the symbol timinginformation.
 29. The method of claim 24, wherein the at least onevirtual transmission periodicity is shorter than the transmissionperiodicity.
 30. An apparatus for communications at a first device,comprising: a processor, and memory coupled to the processor, theprocessor and memory configured to: determine a configuration of anactual transmission periodicity and at least one virtual transmissionperiodicity used by a second wireless device; select a monitoringperiodicity corresponding to the actual transmission periodicity or theat least one virtual transmission periodicity based at least in part onone or more parameters; and monitor for one or more measurement signalstransmitted by the second wireless device over a communication link inaccordance with the selected monitoring periodicity.